


Anatomy Lesson

by basil_leaf



Category: Supernatural
Genre: Alternate Universe - College/University, Alternate Universe - Human, Anatomy, Biting, Blow Jobs, College Student Castiel, Hand Jobs, Light Bondage, Light Dom/sub, M/M, Plot What Plot/Porn Without Plot, Pre-Med Castiel, Rimming, Spanking, Studying
Language: English
Status: Completed
Published: 2016-06-09
Updated: 2016-06-09
Packaged: 2018-07-14 02:36:11
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,731
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7149269
Author URL: https://archiveofourown.org/users/basil_leaf/pseuds/basil_leaf
Summary: <blockquote class="userstuff">
              <p>“You need to study but I want to worship your body.  I figured why not do both at once,” Dean replied with a wink.  “I am going to lick, suck, and kiss my way around your body and you are going to tell me which bone is getting the attention.”  </p><p>Dean wants to fool around but Cas needs to study for an anatomy exam on the human skeleton.  Dean decides to take matters into his own hands and help Cas study.</p>
            </blockquote>





	Anatomy Lesson

**Author's Note:**

> Disclaimer: I'm a musician; I've never had to study anatomy. I embraced my inner Sam and dug into some research but, if you are someone who has studied anatomy, feel free to let me know if I got any of the bones wrong.

“Dean, I really have to study.” Castiel sighed as his boyfriend bent down and kissed his cheek from behind. He loved the attention but Dean had been trying to distract him ever since they had finished dinner.

“Come on, Cas. You’ve been studying this stuff for days. You know it. I know you do,” Dean responded.

“Dean, you can’t know that,” Cas groaned. “There are 206 bones in the adult human body and I need to know all of them. I will never pass anatomy if I don’t pass this test and I will never make it into medical school if I don’t pass anatomy.”

“Cas, man, you are the smartest person I know,” Dean started, “even smarter than my brother, and that’s saying something. You’ve got this.” When Castiel didn’t respond, Dean continued, “You’ve had your nose in that book for so long I’ve almost forgotten what you look like.” Still nothing from Cas; it was time for a new tactic. 

“What if I helped you study?”

Ten minutes later, Castiel found himself naked and strung up in the center of the room he shared with Dean, his arms were stretched toward the ceiling and held in place by the restraints they sometimes pulled out when the couple wanted a little extra spice in the bedroom. The leather cuffs were tied off to a rope Dean had thrown over one of the exposed beams in their bedroom and then anchored to the foot of their bed. Cas waited for Dean to return to the room, unsure of what was coming next or exactly how he had allowed himself to wind up in this position; he had been serious when he told Dean that he needed to study.

Dean sauntered into the room with Cas’ anatomy textbook in hand. “Sorry it took me so long to come back, angel, but if I’m going to help you study I needed to find your book. You can’t draw for shit and I couldn’t tell the diagram you made of a hand apart from the one you tried to draw of a torso.” Dean placed the open book on a small table before rummaging in the nightstand drawer. With a triumphant grin, Dean pulled a cock ring out of the drawer and fastened it tightly around the base of Cas’ already impressive erection. “Wouldn’t want you losing focus during our study session, now would we?” Dean asked.

“Dean, I don’t understand how this is going to help prepare me for my exam.” Cas commented, indicating his bound wrists as best he could.

“You need to study but I want to worship your body. I figured why not do both at once,” Dean replied with a wink. “I am going to lick, suck, and kiss my way around your body and you are going to tell me which bone is getting the attention.” 

Cas whimpered at Dean’s suggested plan. He was sure he wouldn’t be able to focus on bones with Dean’s mouth on him.

“Once I’m satisfied that you know all 206 bones,” Dean continued, ignoring Castiel’s response, “I’ll give number 207 down here all the attention he desires,” he concluded, indicating his boyfriend’s cock.

Dean looked at the book on the table as he unclipped the cuffs holding Cas’ right arm above his head. He licked his lips seductively and brought Castiel’s hand to his mouth. Dean took the very tip of Cas’ middle finger into his mouth, swirled his tongue around the pad, and then sucked on the fingertip, waiting for Cas to correctly name the bone.

“You are actually serious about this, Dean?” Cas asked, which just caused Dean to suck harder. “You are serious. Distal phalange,” he responded, trying to sound as bored as possible while completely aware that his erection made his interest clear.

Dean sucked Cas’s finger further into his mouth, stopping at the second knuckle before slowly pulling his head back and then sinking back down on his boyfriend’s finger.

“Intermediate phalange.” Cas said, keeping his eyes on Dean’s and trying hard to not imagine that it was his cock sliding between his boyfriend’s lips. 

Dean smiled around Castiel’s finger and dipped his head even lower, taking the entire finger into his mouth and massaging the base of the finger with his tongue.

“Pro- proximal phalange,” Cas stuttered. Cas could feel himself getting even harder as Dean worked on his fingers. Three bones in and he was already having trouble keeping it together. If Dean actually kept this up - and Cas was pretty sure he would - Castiel was in for a frustrating night.

Dean released Cas’s finger with a pop and began nuzzling and kissing his palm. As Cas correctly named each bone, Dean worked his way up his boyfriend’s hand and arm, occasionally checking the name of the bones in the textbook on the end table. 

By the time Dean reached his shoulder, Cas was groaning at every lick and kiss. He had never been treated this way. Dean seemed content to basically worship every inch of his body and every touch of his lips or tongue was going straight to Castiel’s cock. 

Cas moaned as Dean’s stubble dragged across his skin when Dean nuzzled his way behind Cas to kiss the back of his shoulder. As soon as Castiel responded with a shaky “scapula,” Dean had his boyfriend’s arm over his head and securely attached to the rope dangling from the ceiling beam once again

“Mmm, very good Cas,” Dean whispered, his voice husky. “No mistakes all the way up your arm. I told you that you knew this stuff but you didn’t want to believe me.” Dean reached a hand down to grasp Castiel’s straining erection, giving it a few pumps as he continued, “let’s see how long you can keep that streak going.”

Cas whimpered when Dean let go of his cock and ran his hands up his sides before raking his nails down his boyfriend’s back. His brain was hazy with lust and he had a feeling that the streak, as Dean had called it, wouldn’t continue much longer.

A shudder ran through Castiel’s body as Dean began to lick and suck at the back of his neck. “Vertebrae,” he responded to the attention.

Dean bit down on Cas’ neck hard enough to leave a mark. “You’ve gotta be more specific, angel,” he rasped against his boyfriend’s neck before he returned to kissing the spot where he had bitten Cas.

Castiel was certain that Dean was trying to drive him insane. The combined sensations of Dean’s mouth, teeth, and stubble against the back of his neck were going straight to his dick and Cas was almost grateful for the cock ring that was keeping him from blowing his load. Almost.

“Come on, Cas. Don’t get lost on me, here. You need to study,” Dean reminded him.

Castiel took a deep breath, trying to ground himself against the onslaught of feelings and sensations Dean’s mouth was causing. “Cervical Vertebrae,” he finally managed.

Dean’s hands dropped to his boyfriend’s hips as he worked his way down the spinal column. Cas returned to his streak of correct answers only stuttering again when he realized Dean was kneeling behind him.

Cas drew a harsh breath when Dean’s hands moved to his ass and began massaging his cheeks. He moaned as Dean’s tongue flicked over his hole. Dean kept teasing his ass and Cas was getting lost in the sensations. When Cas started trying to grind down on his face, Dean pulled away, snickering at his boyfriend’s whimper.

“I think you forgot what we’re doing here, angel,” Dean said looking up at the back of his boyfriend's head. “Now, your fancy text book says that there’s a bone under here.” He punctuated his words with another lick.

Cas was lost in the haze of his lust and he could feel his already rock hard erection getting even fuller. He cried out the first thing that came to his mind when Dean blew a cool stream of air right over his heated hole, “TAILBONE!”

Dean stopped his ministrations and bit down on one of Castiel’s ass cheeks. Cas yelped at the pain-pleasure combination that shot straight to his cock. Had it not been for the leather band strapped tightly around his erection, Castiel would have splattered the wall with his orgasm. 

Dean, almost innocently, returned to torturing his boyfriend’s ass with his tongue as he listened to Castiel babble.

“Oh God, Dean. Please,” Cas exhaled. “Please just… please. I’m so close.”

Dean replied, punctuating each word with another prod of his tongue. “Name,” lick, “The,” lick, “Bone.” After the last word, he plunged his tongue as deep into Castiel as he could, wiggling it around and making Cas squirm and release a deep, chesty moan.

“I don’t… I don’t know. C-can’t think,” Cas babbled.

“Do you want to come, Cas?” Dean asked, mouthing at Castiel’s cheek and rubbing his stubble against where he had bitten his boyfriend’s ass moments ago.

“Yes,” Cas whimpered. “Yes, please.”

“Then we’ve got a lot of studying to get done,” Dean said wickedly before biting down hard on the same spot he had bitten previously.

Cas cried out again, the pain overriding the pleasure just a bit this time. Every time he said a word that wasn’t the correct answer, Dean would either give him a few spanks or another bite before soothing the spot with his tongue and lips. Every few words, Dean would return to the original bite mark to renew and deepen it. In between all of Castiel’s babbling, Dean returned to licking and sucking at his boyfriend’s tight hole.

When Castiel finally managed to squeak out “coccygeal vertebrae,” Dean pulled back and admired his work. His boyfriend’s ass was a lovely shade of pink and decorated with bite marks and small bruises that would heal quickly as well as one darker mark that Cas would probably feel when he sat down for the next day or so. 

Dean stood up and moved around Cas to look at his face. Castiel was sweating and his eyes were wild. “You're doing so well, angel. You’re passing this exam with flying colors,” he told his boyfriend. The sound of his voice seemed to ground Castiel, so Dean continued speaking, “How are your arms? Are they getting tired?”

Cas nodded his head. He hadn't noticed it until Dean asked, but he was starting to get the pins and needles feeling in his arms from having them suspended above his head for so long. 

“Ok, angel, we're not done studying yet but you don't have to stand up for the rest,” Dean said with a smirk. “Will you be ok for two more minutes like this or do you need me to let you down now?”

Cas nodded again. 

“I need you to use your words, Cas. I don't know what that nod meant.” Dean told his boyfriend. 

“2 more minutes.” Cas rasped. 

Dean looked at Castiel with fondness, “God, I love you. I'll be right back.”

Cas smiled as his boyfriend left the room, trusting that he would be back quickly. They had been together for nearly a year but had just gotten to the ‘I love you’ stage. Dean had been hesitant - apart from his brother, no one he'd cared for in his life had ever stuck around - but now that he had started saying it, he said it often and Cas always reveled in the words. 

True to his promise, Dean re-entered their bedroom quickly. He had a bottle of water in his hands that he held up to Castiel’s lips. “Drink,” he commanded gently, and Cas did, grateful for the water he hadn't even realized he wanted. 

When Cas had drunk about half the bottle, Dean put it on the bedside table before returning to Castiel and unhooking the cuffs from the ceiling. He supported part of his boyfriend’s weight as he massaged away the stiffness in his shoulders. Dean then helped Cas over to the bed and had him lie on his back in the center. 

“How do your shoulders feel, Cas?” He asked. 

Cas had come down quite a bit from the lust fueled haze Dean had caused when he was working on his ass. He rolled his shoulders a few times before answering, “they're fine.”

“And the rest of you? You're holding up ok?” Dean checked in, suddenly sounding unsure of himself. 

“I am more than ok, Dean. In fact, I really think I need to get back to studying.” Castiel responded with a mischievous glint in his eye. ‘Good,’ Dean thought, ‘he's enjoying this too.’ 

It was all the assurance Dean needed. He brought Cas’ arms up and attached the cuffs still around his wrists to the upper corners of the bed frame. 

“Well then,” he whispered in Cas’ ear, “let's get back to it.” With that, Dean slid down his boyfriend's body until he was halfway off the bed staring at Castiel’s feet. He knew his boyfriend had extremely ticklish feet and he didn't want to get kicked in the face (they had learned the hard way the kind of damper that could put on a night's plans) so Dean adjusted himself so he was sitting cross legged on the end of the bed with Cas’ feet in his lap. He picked up his left foot and began wiggling Castiel’s toes one by one. Once Cas named the bones in his toes, Dean started massaging his boyfriend's feet as Cas groaned out the rest of the bones. 

After he finished with the feet bones, dwelling a little longer than necessary so that both of Cas’ feet received equal treatment and relaxation, Dean put his boyfriend’s relaxed feet back onto the bed and brought his lips to his left ankle and worked his way up Castiel’s leg with each correctly named bone. 

Cas began to falter again when Dean started sucking at his inner thigh, leaving red marks behind. Dean stopped kissing and nuzzled Cas’ thigh as he said, “stay focused, angel. You're doing so well for me.” He huffed out a breath of warm air over his boyfriend’s straining erection and then went back to teasing the skin above the bone Cas was supposed to name. 

Cas struggled for a full breath and must have taken too long for Dean’s liking. Cas screamed out “FEMUR” as Dean bit down into the flesh of his inner thigh leaving another red mark in his wake. 

Dean hummed in approval as he licked and kissed the bite, soothing away the stinging pain before he moved up to Cas’ pelvis. 

Cas was certain that the only thing keeping him from blowing his load was the damned cock ring Dean had fastened around his dick before he began this torture. He whimpered and moaned as Dean worked on the skin just above his erection. Cas was once again lost in the sensation of Dean’s mouth on his skin, unable to form the words to get his boyfriend to stop teasing and move on. He ended up with a few more small bruises along his hip bones before he managed to eek out “coxal bone.”

Dean worked his way up Cas’ torso, pausing to tease his nipples with his teeth and tongue even after his boyfriend had correctly, and quickly, identified that Dean was working on the skin that covered his ribs. Cas let out another long groan. Every touch of his over sensitized skin was going straight to his cock but Dean’s focus on his nipples felt like lightning coursing through his veins.

When Dean had Cas whimpering and moaning again, he continued his journey upward. It only took one nip at Castiel’s collar bone to ground him and he whispered “Clavicle.”

Dean finished his ascent upwards, lavishing attention on Cas’ jaw (“Mandible”) and his upper lip (“Maxilla”), and feathering kisses across his cheekbones, the bridge of his nose, his forehead, and his temples (“Zygomatic bone, nasal bone, parietal bone, and sphenoid bone”). 

Cas hummed with pleasure at Dean’s soft kisses as he ticked off the facial and cranial bones. Dean missed a few of the smaller bones but Cas catalogued them in his mind. Once Dean finished and Cas named the final bone, he pulled back.

“You were amazing, angel. I’m so proud of you,” Dean told Cas. “You did so well. I told you that you knew this stuff. You know the only times you made any real mistakes were when I was teasing your ass or working close to your cock,” he added before looking pointedly at Castiel’s erection. “Speaking of which, I think you’ve earned your reward.”

With that, Dean stepped away and removed his shirt and pants before once again joining Cas on their bed. He reached up and unhooked the cuffs from the bed frame, massaging his boyfriend’s shoulders again as he lowered his arms. He then removed each of the leather bands from around Castiel’s wrists, kissing the now exposed skin reverently. Dean put the cuffs on the nightstand and then settled in between Cas’ legs. 

Dean just looked at Cas’ erection for a few seconds before turning his eyes to his boyfriend’s face. He loved looking at Castiel from this angle just as much as he knew Cas loved looking down at Dean laying between his legs. 

Dean stuck out his tongue and slowly licked his way up Cas’ shaft, not taking his green eyes off of his boyfriend’s beautiful blues until he sucked the head into his mouth causing Castiel’s head to drop back and a long low moan to escape his throat. The combination of Dean’s mouth and the intense eye contact had been enough to pull Castiel right back to the edge of orgasm. He wanted this to last but he also hoped Dean would remove the God forsaken cock ring soon.

Any rational thought flew out of Cas’ mind when Dean began to bob his head up and down, taking more of his boyfriend’s erection into his mouth with each downward stroke. When Dean had most of Castiel’s cock in his mouth, he hummed in pleasure, feeling his own erection tenting his boxers. 

“Oh God, Dean…” Cas cried weakly as his hips thrusted towards his boyfriend’s mouth. “Dean, please.”

Dean pulled off of Cas’ erection and reached for his hands. He took Castiel’s hands and brought them to his head, encouraging him to thread his fingers in his hair. Dean then reached down and unsnapped the leather around Cas’ cock before plunging down, taking all of his boyfriend into his mouth.

Cas cried out in pleasure at the sudden onslaught of lips and tongue and glorious, glorious suction. He tightened his fingers in Dean’s hair. Dean slowly released Cas’ erection until just the head was in his mouth. He swirled his tongue around the tip and then pushed down, engulfing his boyfriend in his warm, wet mouth. He felt Cas hit the back of his throat and slide past - sometimes not having a gag reflex was a blessing - and Dean swallowed around him.

Cas’ fingernails scratched against Dean’s scalp as he tried to pull him off of his cock but Dean just nuzzled his nose into the thatch of hair at the base of his boyfriend’s erection and swallowed again.

Cas shouted profanities as he came and Dean kept him in his mouth, licking and sucking him through his orgasm. When he was finished, Dean gave Cas a final lick before moving up the bed to lay next to his boyfriend. 

Cas looked at Dean fondly, lifting a hand to his face and swiping his finger across Dean’s bottom lip, collecting the cum that had gathered at the corner of his mouth. He watched Dean’s pupils dilate as he sucked his finger into his own mouth, cleaning himself from his finger.

With one finger still in his mouth, Cas reached into Dean’s boxers and grabbed his erection.

“Cas, this was about you tonight, you don’t have to…” Dean started but Cas cut him off with a kiss.

“I want to, Dean,” he replied. 

Cas paused long enough to lick his hand, giving him a little lubrication, and then continued to stroke Dean’s cock, varying the speed of his movements and the strength of his grip until Dean was writhing under his ministrations and finally spilling over Cas’ hand and onto his stomach with his head thrown back and his face contorted into a silent scream. 

Even though he had come last, Dean came down from the high of the night first. It made sense, he figured as he padded toward their bathroom, since he had purposely kept Cas on edge all night. He quickly cleaned himself up before bringing a warm washcloth into the bedroom to wipe some of the dried sweat from Cas’ brow and his mess from his boyfriend’s hand.

Dean tossed the washcloth in with their dirty clothes and then climbed back into bed. As soon as Dean drew the covers around them, Cas snuggled into his side. He looked up at Dean with groggy eyes and whispered, “I love you, Dean. Thank you for helping me study.”

Dean smiled gently, “I love you, too, angel. You’ll kick that test in the ass tomorrow.”

Cas nuzzled into Dean’s chest as Dean set the alarm for the morning. 

 

~~~~~

 

“Most of you will be disappointed to hear that there was no curve factored into your grades on this exam,” the professor informed the class. An incredulous murmur passed through the class; this test was long and hard and pure memorization and they had been promised a curve. “Settle down,” she continued. “One of your classmates ended up with a perfect score; there were no points to add. Class is dismissed; please pick up your exams on your way out.”

Castiel gathered his papers together and made his way to the front of the room where his professor was handing back exams as the students filed out of the classroom. When he reached her desk, she handed him his paper, adding, “Excellent work, Mr. Novak. Whatever you did to prepare for this exam, keep it up.” Blushing furiously, Cas looked down at the paper in his hand. It was him. Cas was the one who had earned the perfect score.

He rushed home to properly thank his boyfriend.

**Author's Note:**

> I had fun writing this so I hope you had fun reading!! Comments and Kudos are always appreciated and, even though this is a one shot, definitely help with the motivation to keep working on other writing projects.


End file.
